Method for manufacturing a fuel tank and fuel tank

Abstract

The invention relates to a method for manufacturing a fuel tank on the basis of thermoplastic material, the method comprising the following method steps: producing semifinished products in sheet form from a fiber composite material with a matrix of thermoplastic material, laminating the semifinished products with a laminate that comprises at least one barrier layer for hydrocarbons, heat-treating the laminated semifinished products until the thermoplastic material plasticizes, thermoforming the plasticized semifinished products in a thermoforming mold to form shells and joining the shells to form an essentially closed tank.

What is claimed is: 
     
       1. A method for manufacturing a fuel tank, comprising:
 producing a laminate having a plurality of layers, at least one layer of the plurality of layers being a barrier layer for hydrocarbons, 
 producing semifinished products in sheet form of fiber-reinforced material, each semifinished product of the semifinished products comprising woven or laid fibers embedded in a thermoplastic matrix, the fibers comprising at least one of glass fibers, carbon fibers and aramid fibers, 
 after producing the laminate and the semifinished products, heat laminating the semifinished products with the laminate to provide laminated semifinished products, 
 cooling the laminated semifinished products, 
 after cooling the laminated semifinished products, heating the laminated semifinished products until the thermoplastic matrix plasticizes, 
 thermoforming the plasticized laminated semifinished products to form shells, and 
 joining the shells to form the fuel tank. 
 
     
     
       2. The method according to  claim 1 , wherein the laminated semifinished products are only laminated on one side and the laminated side forms an inner side of the fuel tank. 
     
     
       3. The method according to  claim 1 , wherein the shells are each formed with a peripherally encircling flange. 
     
     
       4. The method according to  claim 1 , wherein the step of joining the shells comprises a peripheral welding of the shells. 
     
     
       5. The method according to  claim 4 , wherein, during or after the welding, the flange of the shells is bent over to create an edge-formed seam. 
     
     
       6. The method according to  claim 4 , wherein the flange is provided with a peripheral profile, which reaches around the end faces of the shells. 
     
     
       7. The method according to  claim 6 , wherein the peripheral profile is adhesively bonded or welded to the shells. 
     
     
       8. The method according to  claim 1 , also comprising introducing inserts into the tank before the joining of the shells. 
     
     
       9. The method according to  claim 8 , wherein the inserts are premounted on an insert carrier and in that the insert carrier is inserted into at least one of the shells as a lost carrier. 
     
     
       10. The method according to  claim 9 , wherein the insert carrier is welded or clamped to at least one of the shells. 
     
     
       11. The method according to  claim 1 , wherein, before the joining, at least one shell is provided with at least one lead-through for at least one line connection, into which a connection element is inserted from the inside in a sealing manner. 
     
     
       12. The method according to  claim 1 , wherein the laminate has a maximum thickness of 1.25 mm. 
     
     
       13. The method according to  claim 1 , wherein the barrier layer has a thickness in a range of 50 to 250 micrometers. 
     
     
       14. The method according to  claim 1 , wherein a thickness ratio of the fiber-reinforced material to the laminate for at least one of the shells is in a range of 1.2 to 2. 
     
     
       15. The method according to  claim 1 , wherein the plurality of layers comprise at least five layers with EVOH as the barrier layer. 
     
     
       16. The method according to  claim 15 , wherein the barrier layer is sandwiched between two adhesion promoter layers, and the barrier layer and the two adhesion promoter layers are sandwiched between two covering layers. 
     
     
       17. The method according to  claim 16 , wherein each layer of the two adhesion promoter layers has a maximum thickness of 200 micrometers.